News & Recent Publications

Friday, May 25, 2018

USGS Publication: Data Release In situ recovery (ISR) uranium mining is a technique in which uranium is extracted by a series of injection and recovery wells developed in a permeable sandstone host rock. Chemical constituents (lixiviants) are added to groundwater injection wells to mobilize uranium into groundwater...

This report describes the discovery and geology of two near-surface uranium deposits within calcareous lacustrine strata of Pleistocene age in west Texas, United States. Calcrete uranium deposits have not been previously reported in the United States. The west Texas uranium deposits share characteristics with some calcrete uranium deposits in...

Press Release & Publication The U.S. Geological Survey estimates a mean of 40 million pounds of in-place uranium oxide remaining as potential undiscovered resources in the Southern High Plains region of Texas, New Mexico, and Oklahoma.

USGS Publication: Data Release Grade and tonnage data for calcrete-type surficial uranium deposits found in 11 different countries were compiled. Fifty-eight deposits with reported grade and tonnage, and thirty-five occurrences for which there is no reported resource are tabulated in separate Excel workbook spreadsheets...

Outside Publication: Ore Geology Reviews A genetic deposit model was developed for economic sandstone-hosted uranium deposits that formed in Eocene through Pliocene sandstones in the Texas Coastal Plain. Here 254 uranium occurrences, including 169 deposits, 73 prospects, 6 showings and 4 anomalies, have been identified. About 80 million pounds of U308 have been produced and about 60 million pounds of identified producible U308 remain in place. Uranium is currently being produced from this region, and the deposit model may help identify new mineable deposits.

USGS Publication: Fact Sheet 2016-3074U.S. Geological Survey (USGS) scientists have completed an assessment of the mineral-resource potential, including the uranium potential, of nearly 10 million acres of Federal and adjacent lands in Idaho, Montana, Nevada, Oregon, Utah, and Wyoming. The assessment of these lands, identified as Sagebrush Focal Areas, was done at the request of the Bureau of Land Management. The assessment results will be used in the decision-making process that the Department of the Interior is pursuing toward the protection of large areas of contiguous sagebrush habitat for the greater sage-grouse (Centrocercus urophasianus) in the Western United States. The detailed results of this ambitious study are published in the five volumes of USGS Scientific Investigations Report 2016–5089 and seven accompanying data releases.

Outside Publication: Applied Geochemistry This study investigated the potential for the uranium mineral carnotite (K2(UO2)2(VO4)2x3H2O) to precipitate from evaporating groundwater in the Texas Panhandle region of the United States. Carnotite saturation did occur, and supports the potential for the formation of calcrete-type uranium deposits in the Texas panhandle.

USGS NewsScientists have collected and analyzed 84 environmental samples to establish baseline data prior to any active uranium mining activities at the Canyon Uranium Mine, located south of Grand Canyon National Park. This baseline information will play an important role in assessing if contaminants escape from the mine site and how they would move through the environment once mining operations begin.

Overview

In 2016, there were 99 operable nuclear reactors in the US producing 19% of the nation’s electricity and consuming 47 million pounds of uranium oxide. Just under 5 million lbs. of uranium oxide, approximately 10% of domestic requirements, was produced by US uranium mines in 2016. Domestic production of uranium is from a few mines in Wyoming, Texas, Arizona and Nebraska, and exploration and development of potential uranium mines is widespread throughout the western US and in Virginia. The remaining 90% of uranium required to fuel US reactors is imported, mostly from Kazakhstan, Australia, Canada, Russia and Namibia. In order to assure future domestic supplies of uranium in an ever changing market, there is a continuing need to assess domestic resources and to determine areas most favorable for possible future mining. During the energy crisis of the 1970’s, the US Department of Energy evaluated domestic uranium resources as part of the comprehensive National Uranium Resource Evaluation (NURE) program. This estimate has not been updated since 1980 despite decades of exploration and production. Recognizing the need for an updated quantitative assessment of US uranium resources, the US Geological Survey (USGS) assembled a small group of scientists with the required expertise in 2013. This group prioritized regions and deposit types for assessment based on their potential, and recently completed the first of several planned high priority assessments - an evaluation of potential uranium in the coastal plain of southern Texas. As part of the revitalized uranium project, the USGS is developing methods to expand traditional assessments to include an evaluation of the potential environmental impacts of mining. To produce these expanded assessments the project staff utilizes expertise in uranium geology, hydrogeology, environmental and mining engineering and geochemistry. The USGS uranium project works in partnership with the US Department of Energy, Energy Information Administration (EIA). EIA tabulates and analyzes uranium resource production and reserves in the US, while USGS estimates potential resources. Research by the uranium project has benefited industry, regulators, land owners and land managers. Genetic deposit models help mining companies efficiently explore for additional U resources. The evaluation of groundwater impacts of mining have helped in mitigation efforts and as relevant guidance for regulators. Regional assessments have provided scientific input to help manage multiple uses of public land.

Research

The development of genetic deposit models and evaluation of the environmental impacts of mining require targeted scientific research. This research helps define factors critical to the formation of economic concentrations of uranium, and impacts of mining this uranium. Examples of some uranium research studies that have been recently completed or are in progress are described below. Products of this work are published as peer reviewed articles or fact sheets and presented to scientific or wider non-scientific audiences.

Texas Coastal Plain Sandstone-type Deposit Model

Using GIS technology, multiple sources of data were combined to develop a comprehensive regional genetic model for sandstone-hosted uranium deposits in the Texas Coastal Plain region. The method of integrating this data at a regional scale and at different intervals of geologic time, led to the identification of tracts that were prospective for additional uranium resources. This deposit model was used to estimate potential uranium resources for the region

Southern High Plains Calcrete-type Deposit Model

In 2016 USGS geologists located outcropping calcrete-hosted uranium mineralization in the Texas Panhandle. Groundwater modelling was used to determine that uranium minerals could have formed from the evaporation of modern groundwater. Strontium and uranium isotopes and detailed studies of the unique deposit mineralogy are helping to identify a regional source of uranium and age of mineralization. Combined with understandings of regional geology, and of similar deposits in Australia and Namibia, the first genetic deposit model for this type of uranium deposit in the US now being developed.

Coles Hill Deposit Model

The largest unmined uranium deposit in the US is Coles Hill, located in southwestern Virginia. The original of Coles Hill has been enigmatic since its discovery over 35 years ago. A genetic model is being developed by a research team comprised of geologists at the USGS, the Virginia Museum of Natural History, Virginia Uranium and Virginia Technical University at Blacksburg. The complexity of the deposit is related to multiple tectonic episodes that have impacted this portion of the US, and requires careful integration of the work of geochemists, geochronologists, structural geologists and mineralogists applying multiple analytic techniques. This model will be the basis of an assessment of additional prospective areas and potential uranium resources in the southeastern US.

Uranium Environmental Studies

White Shoes Gymnastics Adults Lxx NIKE 1 White Summit '07 Grey White Air Summit Force Oil Unisex 100 Interdisciplinary uranium environmental studies are being carried out by the USGS scientists and includes the work of geologists, engineers, biologists and hydrologists. Studies of potential mining impacts of uranium are guided by the USGS Environmental Health mission area. Methodology is being developed to integrate the environmental impacts of mining with mineral resources assessments by the USGS Energy and Minerals mission area.

Data

Uranium Geochemical Data

During the late 1970s and early 1980s the Department of Energy, with assistance from the national laboratories and the U.S. Geological Survey, conducted a uranium resource assessment of the U.S., including Alaska (the National Uranium Resource Evaluation or NURE program). As part of this assessment, a hydrogeochemical and stream sediment reconnaissance (HSSR) survey was conducted of nearly the entire U.S. Although originally intended to assist uranium exploration and resource estimates, these data have had a wide variety of uses in exploring for other minerals and providing geochemical baseline information for environmental assessments. The U.S. Geological Survey became the archivist for this data under an agreement with the Department of Energy and has since placed a reformatted version of the entire dataset online. Information about this dataset and access to its components can be found at http://tin.er.usgs.gov/nure/sediment/ (compiled from USGS OFR 97-0492). A great deal of additional mineral resource, geological, geochemical, and geophysical data about the U.S. can be found at http://tin.er.usgs.gov/.

U.S. Atomic Energy Commission Well Log Database

From 1948 to 1956 the U.S. Atomic Energy Commission (AEC) sponsored a broad program of uranium exploration designed to identify resources of uranium for government procurement. The U.S. Geological Survey (USGS) assisted in this effort by providing geologic mapping, airborne radioactivity and other geophysical surveys, geologic framework investigations, and site-specific exploration supported by drilling. Under this program contract drilling was performed by the USGS as well as the U.S. Bureau of Mines (USBM) and numerous private operators. Drilling was concentrated near areas of known or suspected uranium mineralization within the Colorado Plateau, (Colorado, Utah, Arizona, New Mexico), and in Wyoming and South Dakota. AEC-acquired claims, private claims, Indian (Native American) lands, or lands temporarily withdrawn from the public domain were explored. If economic deposits of uranium were discovered the AEC would lease favorable lands under their control to private developers in return for a royalty on ore production. If no economic deposits were identified the withdrawn land was returned to the public domain. Drilling activity and estimates of contained uranium resources were tabulated in various report series published by the AEC (RME, RMO, TM Reports) or USGS (TEM and TEI Reports). The AEC leasing program was terminated in 1962. Some of the AEC lands that were leased for uranium exploration and exploitation were included in a second uranium leasing program that was initiated in 1974 and is administered today by the US Department of Energy (https://energy.gov/lm/services/property-management/uranium-leasing-program/uranium-leasing-program-program-summary)

Additional records of drilling activity in the form of paper and Mylar logs that recorded down-hole lithologic and radiologic information were collected and archived by the AEC. In 1974 when the AEC was abolished, these well logs were retained by the U.S. Energy Research and Development Administration (ERDA), and in 1977 transferred to the U.S. Department of Energy (DOE). The well logs were retained in the Grand Junction, Colorado Field Office of the DOE until 1987 when they were transferred to the USGS in Denver. From 2012 to 2017 the USGS worked with students and interns to scan all of the available logs into digital format for distribution to the public. The available well logs do not encompass all of the drilled holes or all of the exploration areas and are therefore an incomplete collection. However these scans are a significant public resource that is now available online.

Well headers for the logs do not contain sufficient information to georeference the well locations. However, summary reports of drilling activity in the RME, RMO, and TEI series often included maps showing drill hole locations. The scanned logs can be downloaded by state (see below), and a list of references compiled by USGS geologists for the drilled regions is also available for download here. Digital versions of most of these TEI Reports and many other USGS reports are also available from the USGS Publications Warehouse at https://pubs.er.usgs.gov Questions about the Atomic Energy Commission well log database should be directed to Susan Hall, susanhall@usgs.gov, 303-236-1656.

National Geochemical Database (https://pubs.usgs.gov/of/1997/ofr-97-0492/) Downloadable hydrogeochemical and stream sediment data from the Department of Energy’s National Uranium Resource Evaluation program, reformatted and now administered by the USGS.